33 BROMOCRIPTINE USED TO TREAT GIGANTISM IN A TWENTY-THREE MONTH OLD CHILD

Abstract

Bromocriptine (1.25 mg BID) was administered orally to a 23 year old asymptomatic female with accelerated growth and a parasellar tumor (tissue type unknown). Other forms of therapy were refused. Length increased from 76 to 95 cm (22 cm/yr) and weight increased from 10 to 16.25 kg between ages 13 and 23 months. Bone age was 2 years at a chronological age of 18 months. Somatomedin C level was 4.3 U/ml (n=2: normal 0.8 to 2.2 U/ml). Thirteen growth hormone values during overnight monitoring averaged 4.7 ng/ml, range 1.8 to 7.9 ng/ml. Suppression to 5.0 ng/ml was seen during an OGTT. Other neuroendocrine functions were normal. No evidence of isosexual precocity was noted. Somatomedin C levels were 3.2, 2.6, 2.5, 2.4, and 2.2 U/ml on days 1 to 5 of therapy, 2.5 U/ml at 14 days and 2.7 U/ml at 56 days. Length increased from 95 to 97 cm (4.8 cm/yr) during the first 5 months of therapy. CT scan at 5 months shows no change in tumor size. The patient remains asymptomatic.The decrease in levels of somatomedin C associated with a reduction in the growth rate may have resulted from decreased GH production; however, other effects of bromocriptine, such as blocking the peripheral action of somatomedins may be involved.